Method of producing rectifier elements



Feb. 27, 1951 s. TUMULO ma'moo 0F PRODUCING RECTIFIER ELEMENTS 5Sheets-Sheet 1 Filed Oct. 13, 1948 INVENTOR.

A m'mnmyr -dm u M m a F m Feb. 27, 1951 e. TUMULO METHOD OF PRODUCINGRECTIFIER ELEMENTS 3 She ets-She'et 2 Filed Oct. 13, 1948 INVENTOR.

HT'PORNL'Y Feb. 27, 1951 a. TUMULO 2,543,678

METHOD OF PRODUCING RECTIFIER ELEMENTS Filed Oct. 13, 1948 sSheets-Sheet s Patented F eb. 27, 1951 METHOD OF PRODUCING RECTIFIERELEMENTS Gerald 'l umulo, nmimawr, N. Y., assignor to Radio Receptor Co.Inc., New York, N. Y., a

corporation of New York Application October 13, 1948, Serial No. 54,231

Claims.

This invention relates to an improved method and apparatus forefficiently and rapidly producing rectifier elements in multiple.

Broadly, it is an object of this invention to,

provide a method and apparatus for producing rectifier elements inmultiple from a base plate which is later subdivided; wherein a seriesof coatings or layers developing the rectifier effect are superimposedover an enlarged base plate on which there is adheringly mounted aseries of insulating discs, which later serve as masking elements duringthe layer application and as insulating elements in the end product.

Specifically, it is an object of this invention to provide a method ofand apparatus for producing rectifier elements in multiple from a baseplate which comprises successively adheringly mounting a plurality ofinsulating discs in spaced relationship on the surface of a base platesuccessively coating the same with continuous layers of semi-conductivematerial and barrier liquid and discontinuous or spaced areas ofcounterelectrode material, the respective margins between the layers ofcounter-electrode material serving as the severing zone defining theindividual rectifier elements being formed.

Fig. is a transverse sectional view showing a further process step.

Fig. 16 is a plan view illustrating a further step in the process.

Fig. 1'! is a plan view of a completed assembly of rectifiers.

Fig. 18 is a plan view of a completed rectifier section. I

Fig. 19 is a transverse sectional view on the line 19-49 of Fig. 18.

Referring to Figs. 1' through '7. the apparatus for adheringly mountinginmultiple on the base plate masks which serve as insulating discs, in-

, cludes a frame having an upper horizontal rails which extend beyondplate 23.

It is accordingly the object of this invention I to provide a new methodand apparatus for manufacturing rectifiers, and especially adapted tomass production.

This, and other objects, advantages and novel 3 on the of the apparatusof Fig. 1.

Fig. 6 is a vertical sectional view on the line 6-6 of Fig. 5.

Fig. 7 is a vertical sectional view on the line 1-1 of Fig. 6.

Figs. 8 through 12 are partial vertical sectional views illustratingsuccessive steps of the methods. Fig. 13 is a plan view 01' a base plateafter processing in the apparatus of Fig. 1.

Fig. 14 is a transverse sectional view on the line l4l4 of Fig. 13.

shelf 2| supported on legs 22. A relatively heavy, substantially squarebase plate 23 is mounted on shelf 2i. and secured to plate 23 are a pairof horizontally spaced, inverted L-shaped parallel Strips 24 secured tothe extended portions-of rails 25 act as extensions of the bearingsurface 23. Bolts 26 act as outer stops for rails 25, and a thirdinverted L-shaped member 21 extends across the inner ends of the railsand has, near one end, a bore 28 for a purpose to be described.

A slide 3|! is provided, and includes a plate 3|, engaging plate 23 andstrips 24, andan upper plate 32 secured to plate 3| and fitting betweenrails 25. Plate 3| has a reduced extension 33 carrying an operatinghandle 34 for reciprocating slide 30 between a loading position at theouter ends of rails 25 and an operating position at the inner ends ofthe rails. At its inner end, plate 3| carries a finger 36 projectablethrough bar 23 to engage the operator 3! of a microswitch mounted onplate 23. Switch 35 is connected by conductors 33 to an electronic timer(not shown) which controls the operation of the mechanism.

The upper surface of plate 32 has four angle straps 41, one at eachcorner, which serve as location fixers for the metal plate 40 on whichthe rectifiers are formed. In the example shown, twenty-five individualrectifiers are to be formed on plate 40 in five rows of five sectionseach.

A relatively thick, substantially square block 42 rests on rails 25 andhas twenty-five vertical bores 43 each having a bearing bushing 44therein. Each bore is centered with respect to a rectifier section ofplate 40. Resting on the upper surface of block 42 is a plate 46, withits lower surface recessed to form a slit 41 opening transversely of thedirection of movement of slide 30. Plate 45 has twenty-five apertures 48each aligned with a bore 43.

3 Slit or passage 41 extends beyond the outer rows of apertures 48, andis arranged to receive a sheet 50 of masking material, preferably paper,from a roll 5! mounted on a shaft 52 supported in bearings 53. Bearings53 are mounted on the horizontal leg of an L-shaped bracket secured onthe Side of frame 20. A support roller 56 may be mounted in bearings 51between roll 5| and slit 41.

Paper insulating discs 60, which also serve as masks in the piercingstep later described, are punched from adhesive coated insulation sheet50 by means of punches 58 on a vertically reciprocable ram 55 havingguides 6| slidable through apertures in plate or block 23. Each finger58 is slidably engageable in apertures 48 and bores 43. Ram 55 isreciprocated by electrically operable or controlled mechanism connectedto the timer controlled by switch 35.

The operation of the apparatus will now be described. Slide 30 is pulledto the left (Fig. 2) and a metal sheet 40 is located thereon by angles4|. Sheet 50, which is coated with an adhesive on its under surface, ispulled from roll 5| and fed through slit or passage 41 (Fig. 9). Slide30 is then pushed to the right (Fig. 3), whereupon pin or plunger 36passes through bore 28 and engages operator 3'! to activate switch 35.This starts the electronic timer, which controls the reciprocatingmechanism for ram 55.

Ram 55 moves down (Fig. 10) and punches 58 punch discs or masks 60 fromstrip 50, carrying them down through bushings 44 against plate 40. Thetimer maintains the ram in the down position, with punches -58 forcingdiscs 60 against plate 40, for a time sufiicient to assure firmadherence of the discs against the plate. The ram then ascends to theposition of Figs. 8 and 9 and the perforated strip 50 is withdrawn.Slide 30 is moved to the left to the loading position and plate 40, withtwenty-five discs or masks 60 adhered thereto (Figs. 13 and 14) isremoved.

The masked plate is next sprinkled with 9. rectifying material 6| suchas selenium, covering both the surface of the plate and the discs ormasks 60 (Fig. 15). The selenium or the like is then pressed firmly intoadherence with the plate surface and the discs or masks 60, forming acontinuous coating, after which the assembly is annealed in the usualmanner.

Barrier layer liquid is then applied to the annealed selenium surface toform a continuous coating. Thereafter a grid 65 having a series of crossbars bounding openings 66, defining the location and area of thecounter-electrode layer for the respective individual rectifierelements, is placed on the treated surface of the plate andcounter-electrode material applied to each surface within the zones ofthe openings of the grid, thereby forming a series of spaced layers ofcounter-electrode material which are greater in area than the discsaforesaid,

The grid 65 is then removed and the coated base plate may be fed througha shear which cuts the same into strips along and centrally of theparallel margins 6'! from which counter-electrode material has beenmasked by the cross bars bounding the openings 66 as aforesaid, or thebase plate may be fed through a combined punch and shear which seversthe individual rectifiers 10 along the center line of the cross barmasked margins 61 and simultaneously punches apertures 68 throughmasking discs 60 and plate 40. The punching operation leaves an annularinsulation disc 69 around the aperture, between the coatings and thebase, and prevents contact of rough edges of such coatings, particularlythe counterelectrode material, with the base plate at the aperture;since the counter-electrode in no event extends up to the severing line,no problem of short-circuiting can exist at the external peripheraledges of the severed individual rectifier elements. The completedrectifiers may then be electroformed, and assembled on a rod in theusual manner.

The described method and apparatus provide a rectifier in which thesemi-conductor and counter-electrode are in contact throughout theirareas, but separated from the base at the zone of the insulator disc.

While a specific embodiment of the invention has been shown anddescribed in detail to illustrate the application of the principlesthereof, it will be understood that such embodiment is exemplary onlyand that the invention may be otherwise embodied without departing fromsuch principles.

I claim:

1. A method of manufacturing a plurality of selenium or the likerectifiers each of which incorporates as a base a section from a metalplate which is later sub-divided, comprising applying discs ofinsulating material to the surface of the plate in the zone of thecenter of each section, applying to such one surface a continuouscoating of semi-conductive material, applying a continuous barrier layerto the coating, applying a counter-electrode material over the barrierlayer in laterally spaced layers, each of which is superimposed over andis greater in area than the insulating disc, severing the thus treatedplate in the spaces between the counter-electrode layers to formindividual rectifier sections, and piercing the individual sections attheir centers to provide an insulating ring on the base, bounding aformed aperture.

2. A method of manufacturing a plurality of selenium or the likerectifiers eachof which incorporates as a base a section from a metalplate which is later subdivided, comprising adheringly applying discs ofinsulating materialto the surface of the plate in the zone of the centerof each section, applying to such one surface a continuous coating ofsemi-conductive material, applying a continuous barrier layer to thecoating, applying a counter-electrode material over the barrier layer inlaterally spaced layers, each of which is superimposed over ,and isgreater in area than the adhering insulating disc, severing the thustreated plate in the spaces between the counter-electrode layers to formindividual rectifier sections,,and piercing the individual sections attheir centers to provide an insulating ring on the base, bounding aformed aperture.

3. A method of manufacturing a plurality of selenium ,or the likerectifiers each of which incorporates as a base a section from a metalplate which is later subdivided, comprisin adheringly applying discs ofinsulating material to the sur-- face of the,p1ate in the zone of thecenter of each section, applying to such one surface a continuouscoating of semi-conductive material, applying a continuous barrier layerto the coating, applying a counter-electrode material over. the barrierlayer in laterally spaced layers, each of which is superimposed over andis greater in area than the adhering insulating disc, severing the .thus

' treated plate in the spaces between the counterplate in the zone ofthe center of each section,

applying to such one surfacea continuous coating of semi-conductivematerial, applyin a ntin.. uous barrier layer to the coating, mountingover the barrier layer a masking grid having openings delineating ,theareas of the counter-electrode for the individual sections, applyin acoating of a counter-electrode material over the barrier layer withinthe grid openings,,removing the grid, severing the individual rectifiersections along the zones masked by the grid, and piercing the sectionsat their centers to provide aninsulating ring on the base around theformed aperture.

5. a. method of manufacturing a plurality of selenium or the likerectifiers each of which incorporates as a base a section from a metalplate which is later subdivided, comprisin applying discs of insulatingmaterial to the surfaceoi the plate in the zone of the center 01' eachsection. applying to such one surface a continuous coating'Ofsemi-conductive material, applying a continuous barrier layer to thecoating, mounting on the barrier layer a masking grid having openingsdelineating the areas of the counter-electrode for the individualsections, ,applying a coating of counter-electrode material over thebarrier layer within the grid openings, removin the grid, severing theindividual rectifier sections along the zones masked by the grid, andsimultaneously with such severing piercing the sections at their centerstoprovide an insulating ring on the base around the formed aperture.

GERALD 'I'UMULO.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS 2,446,473 Skihker July 6, 1948

